The ordinance, first proposed by the mayor in January, allows homeowners to rent out rooms or a whole home that they live in, or adjacent units in two- or three-family buildings. It bans the listing of “investor units,” homes rented by people who do not live on or near the property.

All owners wanting to list a property on Airbnb will need to register with the city and pay permit fees between $25 and $200, the Herald said.

Airbnb said in a statement last week that it believed the concerns of its hosts were “not heard.

“The new ordinance unfortunately creates a system that violates the privacy of our hosts, and prevents Boston families from making much-needed extra income in one of the country’s most expensive cities,” the statement read.

But as Next City reported in January, housing advocates inside and outside of City Hall maintain that Airbnb and other short-term rental platforms were contributing to the city’s rising housing costs and gentrification. A report by Community Labor United found that 12 percent of Airbnb operators earn 45 percent of the revenue generated, which implies that some hosts own many units. A report produced by the mayor’s office, based on scraping short-term rental sites, estimated that of the 5,500 active listings in the city, 2,000 were “investor units.” Chris English, a policy analyst with the mayor’s office, said they found “power hosts” with dozens of listings and some with as many as 100 listings. The average unit is rented 230 nights per year.

Boston’s Chinatown is a small neighborhood that has been “deeply impacted by gentrification and displacement,” Karen Chen, Chinese Progressive Association’s executive director, told Next City in January. “We’ve been seeing a lot of whole units and whole buildings turned into short rentals that used to house long term residents. People who lived in Chinatown for many years and relied on doctors and social services here are being displaced.”

The mayor’s original proposal, as Next City previously reported, allowed investor units to be rented for up to 90 days a year. That portion of the ordinance was nixed as the rule made its way through the legislative process.

The most notable change, WBUR reports, is that people in two- and three-family homes can rent out their adjacent unit for a full year. (There are no caps on the number of days other types of rentals can be offered, either, according to the most recent version of the bill.)

New Orleans also moved to legitimize Airbnb rentals, but a year after instituting rules governing how homes could be rented on the short-term market, the city council adopted a widespread moratorium on new licenses, a move hailed by housing advocates who said that short-term rentals were driving up rents in that city as well. The New Orleans Gambit reports that Airbnb retaliated by removing city license numbers from its New Orleans listings, making it more difficult for the city to enforce its ordinance, and by deleting a feature from its website that allowed new hosts to automatically apply for a city license, the Times-Picayune reported.